First class and Plausible
Opposite meaning terms
First class
First class noun - Mail that includes letters and postcards and packages sealed against inspection.
Plausible
Plausible adjective - Worthy of being accepted as true or reasonable.
First class is an antonym for plausible.
Nearby Words: plausibly, plausibility
Cite this Source
Plausible and First class. (2016). Retrieved 2026, August 13, from https://thesaurus.plus/related/first_class/plausible
First class & Plausible. N.p., 2016. Web. 13 Aug. 2026. <https://thesaurus.plus/related/first_class/plausible>.
Plausible or First class. 2016. Accessed August 13, 2026. https://thesaurus.plus/related/first_class/plausible.
Google Ngram Viewer shows how "first class" and "plausible" have occurred on timeline